Utility of TERT Promoter Mutations for Cutaneous Primary Melanoma Diagnosis.

Telomerase reverse transcriptase (TERT) promoter mutations are commonly found in malignant melanomas but rare in melanocytic nevi. To assess its potential diagnostic utility for the distinction of melanoma from nevus, we determined the TERT promoter mutation status of 86 primary melanomas, 72 melanocytic nevi, and 40 diagnostically problematic melanocytic proliferations. Of the 86 melanomas, 67 (77.9%) were TERT-positive, defined as harboring a hotspot TERT promoter mutation at positions -124C>T, -124_125CC>TT, -138_139CC>TT, or -146C>T. Of the 72 nevi, only 1 (1.4%) was TERT-positive. Of the 40 diagnostically uncertain melanocytic proliferations, 2 (5.0%) were TERT-positive. TERT positivity as a test for melanoma versus nevus had an accuracy of 87.3% [95% confidence interval (CI), 81.1-92.1], a sensitivity of 77.9% (95% CI, 68.9-85.4), a specificity of 98.6% (95% CI, 95.8-100), a positive predictive value of 98.5% (95% CI, 95.6-100), and a negative predictive value of 78.9% (95% CI, 72.6-85.4). Our results indicate that hotspot TERT promoter mutation status may be a useful ancillary parameter for the diagnosis of melanoma. In particular, the high specificity of these mutations for melanoma indicates the presence of a TERT promoter mutation in a melanocytic neoplasm associated with diagnostic controversy, or uncertainty should increase concern for a melanoma.

Identification of a Robust Methylation Classifier for Cutaneous Melanoma Diagnosis.

Early diagnosis improves melanoma survival, yet the histopathological diagnosis of cutaneous primary melanoma can be challenging, even for expert dermatopathologists. Analysis of epigenetic alterations, such as DNA methylation, that occur in melanoma can aid in its early diagnosis. Using a genome-wide methylation screening, we assessed CpG methylation in a diverse set of 89 primary invasive melanomas, 73 nevi, and 41 melanocytic proliferations of uncertain malignant potential, classified based on interobserver review by dermatopathologists. Melanomas and nevi were split into training and validation sets. Predictive modeling in the training set using ElasticNet identified a 40-CpG classifier distinguishing 60 melanomas from 48 nevi. High diagnostic accuracy (area under the receiver operator characteristic curve = 0.996, sensitivity = 96.6%, and specificity = 100.0%) was independently confirmed in the validation set (29 melanomas, 25 nevi) and other published sample sets. The 40-CpG melanoma classifier included homeobox transcription factors and genes with roles in stem cell pluripotency or the nervous system. Application of the 40-CpG melanoma classifier to the diagnostically uncertain samples assigned melanoma or nevus status, potentially offering a diagnostic tool to assist dermatopathologists. In summary, the robust, accurate 40-CpG melanoma classifier offers a promising assay for improving primary melanoma diagnosis.

Hair Follicle Nevus Located on the Chin of an Infant: Case Report and Review of Literature.

Hair follicle nevi are rare, benign, congenital hamartomas that usually occur in the distribution of the first brachial arch. Histopathologically, the distinction between hair follicle nevus, trichofolliculoma, and accessory tragus has recently come into question, and it may be that they are all on a spectrum of the same condition. We report the case of a 7-day-old boy who presented with a "tag"-like lesion on his midline chin that had been present since birth. Biopsy of the lesion proved it to be a hair follicle nevus.

Imiquimod-induced subacute cutaneous lupus erythematosus-like changes.

Imiquimod is a topical immunomodulator used to treat genital warts and cutaneous malignancies that exerts its effects via induction of proinflammatory cytokines through activation of toll-like receptor (TLR) 7. Although subacute cutaneous lupus erythematosus (SCLE) has been reported in association with multiple systemic medications, SCLE in patients treated with topical agents has not been widely reported. We report the case of a 50-year-old woman with local induction of lesions that clinically and histologically resembled SCLE following treatment with topical imiquimod.

Mucosal pemphigus vulgaris anti-Dsg3 IgG is pathogenic to the oral mucosa of humanized Dsg3 mice.

There are two major clinical subsets of pemphigus vulgaris (PV)-mucosal PV (mPV) and mucocutaneous PV (mcPV). The mPV subset exhibits anti-human desmoglein (Dsg) 3 autoantibodies that fail to recognize murine Dsg3 (mDsg3); thus, passive transfer experiments of mPV IgG into wild-type (WT) mice have been unsuccessful at inducing disease. We therefore generated a fully humanized Dsg3 (hDSG3) murine model utilizing a hDsg3 transgenic animal crossed to the mDsg3 knockout line. Expression of hDsg3 in the mucosa rescues the mDsg3 knockout phenotype. Well-characterized mPV sera bind mucosal epithelia from the hDsg3 mice, but not mucosal tissues from WT mice, as detected by indirect immunofluorescence (IF). The majority of mPV sera preferentially recognize hDsg3 compared with mDsg3 by immunoprecipitation as well. Passive transfer of mPV IgG into adult hDsg3 mice, but not WT mice, induces suprabasilar acantholysis in mucosal tissues, thus confirming the pathogenicity of mPV anti-hDsg3 IgG in vivo. Human anti-hDsg3 antibodies are detected in perilesional mucosa as well as in sera of recipient mice by IF. These findings suggest that the Dsg3 epitopes targeted by pathogenic mPV IgG are human specific. This hDsg3 mouse model will be invaluable in studying the clinical transition from mPV to mcPV.

Dermatomyositis as a presentation of neuromyelitis optica spectrum disorder.

IMPORTANCE: This is the first report of neuromyelitis optica spectrum disorder (NMOSD) associated with dermatomyositis (DM). REPORT: A 40year-old Caucasian female presented with 6months of worsening fatigue, rash, acute weakness worse in her lower extremities, and urinary retention. She was found to have both NMOSD and anti-melanoma differentiation-associated gene (MDA)5 positive DM with interstitial lung disease (ILD). She was treated aggressively and she regained her ability to ambulate. CONCLUSION: We recommend considering NMOSD in the differential diagnosis of patients with DM and other autoimmune disorders that also present with clinical signs of myelopathy.

9 tips to help prevent derm biopsy mistakes.

The authors--with expertise in dermatology and pathology--provide pointers that can help you improve your approach to skin biopsy.

Mutation-specific RAS oncogenicity explains NRAS codon 61 selection in melanoma.

UNLABELLED: NRAS mutation at codons 12, 13, or 61 is associated with transformation; yet, in melanoma, such alterations are nearly exclusive to codon 61. Here, we compared the melanoma susceptibility of an NrasQ61R knock-in allele to similarly designed KrasG12D and NrasG12D alleles. With concomitant p16INK4a inactivation, KrasG12D or NrasQ61R expression efficiently promoted melanoma in vivo, whereas NrasG12D did not. In addition, NrasQ61R mutation potently cooperated with Lkb1/Stk11 loss to induce highly metastatic disease. Functional comparisons of NrasQ61R and NrasG12D revealed little difference in the ability of these proteins to engage PI3K or RAF. Instead, NrasQ61R showed enhanced nucleotide binding, decreased intrinsic GTPase activity, and increased stability when compared with NrasG12D. This work identifies a faithful model of human NRAS-mutant melanoma, and suggests that the increased melanomagenecity of NrasQ61R over NrasG12D is due to heightened abundance of the active, GTP-bound form rather than differences in the engagement of downstream effector pathways. SIGNIFICANCE: This work explains the curious predominance in human melanoma of mutations of codon 61 of NRAS over other oncogenic NRAS mutations. Using conditional "knock-in" mouse models, we show that physiologic expression of NRASQ61R, but not NRASG12D, drives melanoma formation.

Validation of the VE1 immunostain for the BRAF V600E mutation in melanoma.

BACKGROUND: BRAF mutation status, and therefore eligibility for BRAF inhibitors, is currently determined by sequencing methods. We assessed the validity of VE1, a monoclonal antibody against the BRAF V600E mutant protein, in the detection of mutant BRAF V600E melanomas as classified by DNA pyrosequencing. METHODS: The cases were 76 metastatic melanoma patients with only one known primary melanoma who had had BRAF codon 600 pyrosequencing of either their primary (n = 19), metastatic (n = 57) melanoma, or both (n = 17). All melanomas (n = 93) were immunostained with the BRAF VE1 antibody using a red detection system. The staining intensity of these specimens was scored from 0 to 3+ by a dermatopathologist. Scores of 0 and 1+ were considered as negative staining while scores of 2+ and 3+ were considered positive. RESULTS: The VE1 antibody showed a sensitivity of 85% and a specificity of 100% as compared to DNA pyrosequencing results. There was 100% concordance between VE1 immunostaining of primary and metastatic melanomas from the same patient. V600K, V600Q, and V600R BRAF melanomas did not positively stain with VE1. CONCLUSIONS: This hospital-based study finds high sensitivity and specificity for the BRAF VE1 immunostain in comparison to pyrosequencing in detection of BRAF V600E in melanomas.

Case report of drug rash with eosinophilia and systemic symptoms demonstrating human herpesvirus-6 reactivation.

Drug rash with eosinophilia and systemic symptoms (DRESS) is a severe drug-induced hypersensitivity syndrome that presents with diffuse cutaneous eruptions, fever, and multiorgan involvement. Here we present a pediatric case of DRESS complicated by human herpesvirus (HHV)-6 reactivation. After 1 week of sulfasalazine, our patient developed a diffuse morbilliform eruption. Sulfasalazine was discontinued. The patient presented to the emergency department soon thereafter with worsening eruption, fever, rigors, facial edema, and lymphadenopathy. Methylprednisolone was initiated. Peripheral smear did not demonstrate eosinophilia but showed toxic granulation with atypical lymphocytes. Transaminase levels and white blood cell count quickly became elevated, with increased eosinophils, suggesting DRESS. During the methylprednisolone taper, our patient experienced symptom exacerbation, acute hepatitis, and HHV-6 seroconversion, indicating HHV-6 reactivation as the cause. As demonstrated by our patient, a decelerated methylprednisone taper is important because of potential symptom flaring during taper. Additionally, in the care of individuals with DRESS, HHV-6 is often tested for upon admission and not repeated. Delay in the rise of titers necessitates repeat testing.

Granuloma annulare arising in association with pulmonary coccidioidomycosis.

Granuloma annulare (GA) is a reactive process in the dermis, related to degeneration of collagen. It may occur as an idiopathic phenomenon or in conjunction with a myriad of systemic conditions, including infectious disease. We report an interesting case of GA precipitated by pulmonary coccidioidomycosis.

Lupus erythematosus panniculitis in children: report of three cases and review of previously reported cases.

Lupus erythematosus panniculitis (LEP) is a rare finding in children, with only 12 fully reported prior cases in the English literature. We describe three cases of LEP in children younger than 18 and compare them to previous cases reported in the literature. We examine laboratory tests performed, biopsy results, age at onset and diagnosis, presence or absence of systemic symptoms, and outcomes after treatment. It is unknown what the risk is of these patients developing future systemic lupus erythematosus. We also discuss the relevance of subcutaneous panniculitis-like T-cell lymphoma, because the clinical and pathologic pictures are similar in presentation.

Spitz nevi, atypical spitzoid neoplasms, and spitzoid melanoma.

Spitz nevi and melanoma represent benign and malignant counterparts commonly coupled in the same differential diagnosis. The precise distinction between the two entities remains an ongoing challenge in dermatopathology and surgical pathology. In past years, considerable work has been devoted to the assembly of criteria to permit exact diagnosis. Although diagnostic accuracy has improved, many lesions remain challenging to classify based solely upon conventional microscopic criteria. In this article, the clinical and histopathological attributes of Spitz nevi and spitzoid melanoma are reviewed. Lesions that cannot be definitively classified based solely upon conventional microscopic criteria are referred to as atypical spitzoid neoplasms, which the authors view as a provisional diagnostic category rather than as a formal disease entity. Molecular assessment by way of comparative genomic hybridization or fluorescence in situ hybridization is increasingly used to facilitate assessment of this challenging differential and is especially germane to the evaluation of ambiguous lesions.

Subcutaneous Metastatic Adenocarcinoma: An Unusual Presentation of Colon Cancer - Case Report and Literature Review.

Subcutaneous metastasis from a visceral malignancy is rare with an incidence of 5.3%. Skin involvement as the presenting sign of a silent internal malignancy is an even rarer event occurring in approximately 0.8%. We report a case of a patient who presented to her dermatologist complaining of rapidly developing subcutaneous nodules which subsequently proved to be metastatic colon cancer, and we provide a review of the literature.

How informative are dermatopathology requisition forms completed by dermatologists? A review of the clinical information provided for 100 consecutive melanocytic lesions.

BACKGROUND: Accurate clinicopathologic correlation can be crucial to arriving at the correct microscopic diagnosis. OBJECTIVE: We reviewed the clinical information provided on the dermatopathology requisition forms for melanocytic lesions submitted by community dermatologists. METHODS: The clinical information provided and the microscopic diagnoses rendered were recorded in a retrospective, unblinded fashion for 100 consecutive melanocytic lesions submitted as wet tissue to our dermatopathology department. RESULTS: Biopsy specimens were received from 60 community dermatologists and 5 nurse practitioners/physician assistants. Clinical morphology (ie, papule) was provided in 33% of cases. With respect to the ABCDE criteria, 55% of cases had none, 12% had one criterion, 21% had two criteria, 10% had 3 criteria, 2% had 4 criteria, and none had all 5 criteria. No forms stated whether the biopsy specimen was a partial or complete sampling of the lesion. Asymmetry was provided 4% of the time, border irregularity 8%, color 39%, diameter 22%, and evolution 10%. A family or personal history of melanoma was provided in 8% of cases. No requisition forms mentioned the "ugly duckling" sign. Dermatoscopy information and a clinical photograph were provided once each. In 19 cases, the only information on the requisition form was one of the phrases: "r/o atypia," "r/o atypical nevus," "r/o Clark's," or "r/o dysplastic nevus." In 10 cases, the only information was "r/o nevus." LIMITATIONS: Only 100 consecutive melanocytic lesions were studied in a retrospective, unblinded fashion. CONCLUSION: Important clinical information regarding pigmented lesions is often not provided on the requisition form. Potential reasons for this deficit and suggestions for improvement are discussed.

Dermal mucinosis as a sign of venous insufficiency.

Dermal mucinoses are a heterogeneous group of disorders characterized by abnormal deposition of dermal mucin, an amorphous substance composed of hyaluronic acid and sulfated glycosaminoglycans. We describe two cases of dermal mucinosis in the setting of chronic venous insufficiency. Both patients presented with painful, edematous lower extremity plaques. Biopsies of all lesions showed striking dermal mucin deposition, a slight increase in small blood vessel density, slightly thickened vessel walls and no inflammation. Neither patient showed laboratory or clinical findings consistent with a secondary mucinosis such as thyroid dysfunction, lupus erythematosus, dermatomyositis, scleroderma, granuloma annulare, graft-vs.-host disease or mucin deposition post-ultraviolet or photochemotherapy treatment. Both patients were diagnosed with localized cutaneous mucinosis secondary to venous insufficiency. The clinicopathological features of this entity are described, and a pathogenic mechanism is proposed.

Eruptive angiokeratomas on the glans penis.

Angiokeratomas are benign proliferations of dilated thin-walled blood vessels in the upper dermis with overlying epidermal hyperkeratosis. There are several clinical variants of angiokeratomas: 1. Fordyce: smooth reddish-purple papules on scrotum or vulva; 2. Mibelli: hyperkeratotic papules on fingers or toes, solitary, multiple, or circumscriptum (grouped papules usually on an extremity); 4. angiokeratoma corporis diffusum, widespread papules that are a manifestation of one of several inherited lysozomal storage diseases. Herein, we report a rare case of multiple angiokeratomas of Fordyce on the corona of the glans penis.

Desmoplastic cellular neurothekeoma: Clinicopathological analysis of twelve cases.

BACKGROUND: Cellular neurothekeoma is a benign lesion most commonly found on the face and upper extremities in the first two decades of life. METHODS: Retrospective clinicopathologic review of 12 examples of cellular neurothekeoma typified by prominent stromal sclerosis, a distinctive variant that we refer to as desmoplastic cellular neurothekeoma. RESULTS: The mean age was 30 years (range, 3-55 years, 3 males, 9 females). The site was the head and neck in 3 cases, upper extremity in 4, lower extremity in 2, and trunk/abdomen in 3. All cases showed fascicles of slightly spindled and polygonal cells arrayed haphazardly in a prominent sclerotic background in the dermis and superficial subcutis. The cells displayed pale cytoplasm with indistinct membranes and vesicular nuclei with a single nucleolus. Lesional cells expressed NKI/C3, laminin, CD68, and CD10 and lacked expression of S-100 protein, EMA, and CD34. Clinical follow up was available on 10 cases with a mean duration of 24 months (range, 11-42 months) with no local recurrences or metastases. CONCLUSIONS: The immunohistochemical staining pattern, clinical findings, and benign nature are similar to "conventional" cellular neurothekeomas. The differential diagnosis includes desmoplastic melanocytic lesions, desmoplastic spindle cell carcinoma, dermatofibroma, "immature" scar, plexiform fibrohistiocytic tumor, perineurioma, and piloleiomyoma.